Department of Biological Sciences, Hunter College, City University of New York, 904 North Building, 695 Park Avenue, New York, NY, 10065, USA.
Manhattan/Hunter Science High School, New York, NY, USA.
Sci Rep. 2022 Jul 7;12(1):11515. doi: 10.1038/s41598-022-14598-9.
The concept of DNA transfer between bacteria was put forth by Griffith in 1928. During the dawn of molecular cloning of DNA in the 1980s, Hanahan described how the transformation of DNA plasmids into bacteria would allow for cloning of DNA fragments. Through this foundational work, it is widely taught that a typical transformation produces clonal bacterial colonies. Using low concentrations of several plasmids that encode different fluorescent proteins, under the same selective antibiotic, we show that E. coli bacteria readily accept multiple plasmids, resulting in widespread aclonality and reveal a complex pattern of colony development. Cotransformation of plasmids occurs by either CaCl or by electroporation methods. A bacterium rod transformed with three plasmids-each expressing a high level of a unique fluorescent protein-and replated on agar, appears to reassign a random number of the three fluorescent plasmids to its daughter cell during cell division. The potential to simultaneously follow multiple lineages of clonally related bacteria in a bacteria colony would allow for mosaic analysis of gene function. We show that clonally related bacterium rods self-organize in a fractal growth pattern and can remain linked during colony development revealing a potential target against microbiota growth.
格里菲斯于 1928 年提出了细菌间 DNA 转移的概念。在 20 世纪 80 年代 DNA 克隆分子生物学的黎明时期，汉纳汉描述了如何将 DNA 质粒转化为细菌，从而实现 DNA 片段的克隆。通过这项基础工作，人们普遍认为典型的转化会产生克隆细菌集落。我们使用低浓度的几种质粒，这些质粒编码不同的荧光蛋白，在相同的选择性抗生素下，我们展示了大肠杆菌很容易接受多个质粒，导致广泛的无性繁殖，并揭示了菌落发育的复杂模式。质粒的共转化可以通过氯化钙或电穿孔方法进行。用三个质粒转化的细菌杆状细胞 - 每个质粒都表达一种高水平的独特荧光蛋白 - 并在琼脂上重新接种平板，在细胞分裂过程中，似乎会将三个荧光质粒中的任意数量重新分配给其子细胞。在细菌菌落中同时跟踪多个克隆相关细菌谱系的潜力将允许对基因功能进行马赛克分析。我们表明，克隆相关的细菌杆状细胞自行组织成分形生长模式，并且在菌落发育过程中可以保持连接，这揭示了针对微生物群生长的潜在目标。
